8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f27 when write [fee04f27] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 13350 Comm: syz.2.2455 Not tainted 6.16.0-syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:88 [inline] PC is at parport_attach drivers/comedi/drivers/comedi_parport.c:289 [inline] PC is at parport_attach+0x174/0x1d0 drivers/comedi/drivers/comedi_parport.c:224 LR is at parport_attach drivers/comedi/drivers/comedi_parport.c:289 [inline] LR is at parport_attach+0x164/0x1d0 drivers/comedi/drivers/comedi_parport.c:224 pc : [<813ab000>] lr : [<813aaff0>] psr: 60000013 sp : dfabdd30 ip : dfabdd30 fp : dfabdd54 r10: 82b16f00 r9 : 00000003 r8 : 8409e3c0 r7 : dfabdd90 r6 : 8409e3c0 r5 : 00000000 r4 : 00000000 r3 : fee04f27 r2 : 81e15444 r1 : 00000001 r0 : 813aac70 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85c44200 DAC: fffffffd Register r0 information: non-slab/vmalloc memory Register r1 information: non-paged memory Register r2 information: non-slab/vmalloc memory Register r3 information: 0-page vmalloc region starting at 0xfee00000 allocated at pci_reserve_io+0x0/0x38 arch/arm/mm/mmu.c:1055 Register r4 information: NULL pointer Register r5 information: NULL pointer Register r6 information: slab kmalloc-192 start 8409e3c0 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfabc000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r8 information: slab kmalloc-192 start 8409e3c0 pointer offset 0 size 192 Register r9 information: non-paged memory Register r10 information: non-slab/vmalloc memory Register r11 information: 2-page vmalloc region starting at 0xdfabc000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r12 information: 2-page vmalloc region starting at 0xdfabc000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Process syz.2.2455 (pid: 13350, stack limit = 0xdfabc000) Stack: (0xdfabdd30 to 0xdfabe000) dd20: dfabde4c dfabdd40 829cf8ec 829cf8ec dd40: 81e15904 8409e404 dfabdd8c dfabdd58 813a7098 813aae98 b5403587 00000000 dd60: 84aea400 200000c0 8409e3c0 b5403587 200000c0 84aea400 40946400 00000003 dd80: dfabde4c dfabdd90 813a2c18 813a6f9c 656d6f63 705f6964 6f707261 00007472 dda0: 00000000 00004f27 00000000 00000004 00000004 00000005 00000005 00000004 ddc0: 00000007 54c6cff3 000000fd 00000002 00000001 00000001 00000001 00000006 dde0: 00000101 00000000 0000027f 00000003 40000003 00000089 0000caa3 00000000 de00: 20001e5b 00000003 00000e66 00000004 00000008 00004086 00000000 fffffff8 de20: 00000000 96310b0f 00000000 855cc000 8409e3c0 200000c0 200000c0 84aea400 de40: dfabdf14 dfabde50 813a3be4 813a2b24 00000000 00000000 00000000 96310b0f de60: 00000000 00000000 8247054c 0000005f 83deda58 8409e3f0 840af3b4 84aea400 de80: dfabdee4 dfabde90 8079794c 8078dcb0 00000064 00000001 00000000 dfabdeac dea0: 85778cd0 8342acc0 00006400 0000000b dfabdea0 00000000 00000000 96310b0f dec0: 855cc000 40946400 200000c0 200000c0 855cc000 00000003 dfabdef4 dfabdee8 dee0: 80797a6c 96310b0f dfabdf14 40946400 00000000 855cc001 200000c0 855cc000 df00: 00000003 84aea400 dfabdfa4 dfabdf18 8056cf08 813a3614 ecac8b10 84aea400 df20: dfabdf3c dfabdf30 81a388b8 81a38788 dfabdf54 dfabdf40 8025e490 8028ef8c df40: dfabdfb0 40000000 dfabdf84 dfabdf58 802229ec 8025e44c 00000000 8281cddc df60: dfabdfb0 0014c820 ecac8b10 80222940 00000000 96310b0f dfabdfac 00000000 df80: 00000000 002f6308 00000036 8020029c 84aea400 00000036 00000000 dfabdfa8 dfa0: 80200060 8056cde4 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f500bc dfe0: 76f4fec0 76f4feb0 0001948c 001322c0 60000010 00000003 00000000 00000000 Call trace: [<813aae8c>] (parport_attach) from [<813a7098>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1006) r6:8409e404 r5:81e15904 r4:829cf8ec [<813a6f90>] (comedi_device_attach) from [<813a2c18>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:84aea400 r7:200000c0 r6:b5403587 r5:8409e3c0 r4:200000c0 [<813a2b18>] (do_devconfig_ioctl) from [<813a3be4>] (comedi_unlocked_ioctl+0x5dc/0x1c24 drivers/comedi/comedi_fops.c:2173) r8:84aea400 r7:200000c0 r6:200000c0 r5:8409e3c0 r4:855cc000 [<813a3608>] (comedi_unlocked_ioctl) from [<8056cf08>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813a3608>] (comedi_unlocked_ioctl) from [<8056cf08>] (do_vfs_ioctl fs/ioctl.c:552 [inline]) [<813a3608>] (comedi_unlocked_ioctl) from [<8056cf08>] (__do_sys_ioctl fs/ioctl.c:596 [inline]) [<813a3608>] (comedi_unlocked_ioctl) from [<8056cf08>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:584) r10:84aea400 r9:00000003 r8:855cc000 r7:200000c0 r6:855cc001 r5:00000000 r4:40946400 [<8056cdd8>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfabdfa8 to 0xdfabdff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f500bc dfe0: 76f4fec0 76f4feb0 0001948c 001322c0 r10:00000036 r9:84aea400 r8:8020029c r7:00000036 r6:002f6308 r5:00000000 r4:00000000 Code: e596306c e3a04000 e7f33053 e2433612 (e5c34000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e596306c ldr r3, [r6, #108] @ 0x6c 4: e3a04000 mov r4, #0 8: e7f33053 ubfx r3, r3, #0, #20 c: e2433612 sub r3, r3, #18874368 @ 0x1200000 * 10: e5c34000 strb r4, [r3] <-- trapping instruction